Film archival storage and preservation system

ABSTRACT

An archival film storage container and a system of using the same for the archival storage and preservation of motion picture and photographic film and paper, videotape, magnetic tape and the like are disclosed, wherein the container is perforated to permit off gassing released from material archived within the closed storage container to permeate outside the container. A fire retardant filter material may be located over the inner surface of the archival container, covering all of the perforations and providing a filtering function by preventing particulate matter from entering the closed container.

[0001] This application claims the priority of U.S. Provisional Patent Application No. 60/267,929, filed Feb. 9, 2001.

TECHNICAL FIELD

[0002] The present invention relates generally to archival storage systems, in particular, to perforated, fire retardant archival storage containers and a system of using the same in the archival storage and preservation of reels of motion picture film, videotape, magnetic tape and the like, wherein off gasses will be formed within the storage containers.

BACKGROUND OF THE INVENTION

[0003] Four principal factors contribute to the deterioration of photographic films and papers: poor environmental storage conditions, the presence of residual photographic processing chemicals or the use of exhausted processing chemicals, poor archival storage containers and shelving conditions, and rough or inappropriate handling that results in unnecessary wear and tear. While the present invention is generally directed towards improving archival storage and preservation for reels and sheets of photographic film and the like, the other principal factors must be taken into consideration if the preservation of the archived film is to be effective.

[0004] Examples of environmental factors that affect the preservation of photographic materials and the like are relative humidity, temperature, air pollution, light, and housekeeping practices. All photographic materials are sensitive to high, low, and fluctuating relative humidity (RH), which is a measure of how saturated the air is with moisture. High RH can affect all components of photographs. High RH causes a gelatin binder to become soft and sticky, making it vulnerable to mechanical damage and image deterioration. Low RH can cause the binder to shrink and crack and the secondary support to curl.

[0005] High temperature speeds up the rate of deterioration. The higher the temperature, the faster film or a photograph deteriorates, especially at high RH levels. High temperature and high humidity conditions may contribute to the growth of microscopic mold spores on the image-containing layer. Once active mold infests photographic materials it is usually impossible to remove without damaging the photograph. Mold tends to develop when the temperature is above 75-80° F. and the RH is greater than 60%.

[0006] Temperature and RH fluctuations, or “cycling”, result in chemical and mechanical changes that are especially damaging to film and photographs. Cycling promotes the movement of moisture in and out of film and photographs, speeds up the rate of chemical deterioration, and promotes the breakdown of the binder that holds the final image material to the support. When both humidity and temperature are high, or when materials undergo temperature and RH cycling, structural damage and the rate of chemical deterioration are greatest.

[0007] Historically, standard archival practice has been to store photographic films in air- and light-tight containers of the kind in which unexposed films are sold.

[0008] Air pollution external to the archival storage containers but which enter the container during handling, and off gasses produced from the films within such sealed containers, attack film and photographs in the form of: (1) oxidant gases, (2) particulate matter, (3) acidic and sulfiding gases, and/or (4) environmental fumes. Oxidant gases are composed primarily of pollution created by burning fossil fuels such as coal and oil. Nitrogen oxides (oxide and dioxide) and ozone are the two main gases that threaten film and photographic images. Nitrogen oxides are produced by combustion, as in automobile engines. Oxidant gases cause film and photographic images to fade by chemically interacting with the silver image material.

[0009] Particulate matter and dust particles, such as soot and ash particles from manufacturing processes, exist in abundance outdoors and can enter an archival storage area through heating and cooling ducts, doors, and windows. Particulates, which may be greasy, abrasive, and chemically or biologically active, settle on shelves and on collection materials and create dust that is spread to other materials when they are handled. The by-products of combustion combined with moisture in the atmosphere pose another risk to photographic materials. When fossil fuels such as coal and oil are burned, nitrogen and sulfur dioxide are produced. The reaction of nitrogen and sulfur dioxide with water in the atmosphere produces nitric and sulfuric acid. These acids attack all components of photographs. Therefore, air entering an archival storage area should be filtered and purified to remove gaseous and particulate matter.

[0010] Insects (silverfish, cockroaches, beetles) and rodents (rats, mice, and squirrels) are all attracted to film and photographic materials, especially because of the gelatin layers. In addition to eating the materials, the insects and rodents also foul the storage area and materials with their droppings, and make nests that can be difficult to locate and remove. Floors, shelves, boxes, and cabinets should be dusted or vacuumed, or both, on a regular basis. Collection materials should not be stored directly on the floor where they are more likely to be damaged by insects and rodents or water leaks.

[0011] Not unlike other materials containing color dyes, all processed photographic films are subject to fading, particularly integral color positive films, such as Ektachrome®, Ansco®, or Agfa® brand films, that may not have been processed entirely to specification. As with all other materials, this fading—as well as other chemical and physical deterioration—are impossible to stop entirely. With proper care, handling and archival storage, the rate of deterioration can be slowed and the usable life of a film can be extended significantly, over several decades.

[0012] For 35 mm nitrate-based film, as for all other materials, the rate of deterioration depends largely on the conditions under which it is stored, how it is handled, and on the ingredients and care used in manufacturing its base. If a film is not marked as safety film, it should be considered to be nitrate until examined for nitrate markings or tested chemically. Cans of nitrate film that have remained closed for some time should be opened in unconfined, well-ventilated spaces. If gasses given off by decomposing nitratebased film are trapped in a confined space—such as typically occurs in a sealed can—they can ignite at temperatures above 100° F. Nitrate film is highly flammable, ignites easily, and cannot be extinguished after burning has begun. Additionally, off gases sealed within the container can cause substantial degradation of film stored therein. Ideally, temperature and humidity levels for archival storage of motion picture film should be kept constant and at a maximum of 50° F./10° C. and 50% RH.

[0013] Acetate film, like nitrate film, is subject to continuous decomposition, especially if kept under poor storage conditions. Eventually acetate-based film will suffer from the so-called “vinegar syndrome,” derived from the strong acetic acid (like vinegar) smell the film emits as it deteriorates. One advantage acetate film has over nitrate film is that it is not truly flammable, that is if subjected to a flame it just smolders.

[0014] Polyester-based film is chemically more stable than nitrate and acetate film. The emulsion layer on all film bases can shrink over time, especially on the bases of nitrate and acetate film. Since polyester bases do not shrink as much as the emulsion layers, a concern exists that expansion and contraction of the emulsion layer on a polyester base will eventually cause it to separate from the base.

[0015] When film reels are stored, they should always be wound evenly, and never too tightly, with the emulsion side out. Currently, motion picture film reels are stored in sealed substantially air-tight metal or plastic film storage cans and boxes. Decomposing nitrate films and acetate films suffering from the vinegar syndrome must always be stored separately from one another and apart from other films. Common types of film damage include, but are not limited to shrinkage, brittleness, buckling, scratching, and perforation damage. Nitrate and acetate films can shrink and/or become brittle, through loss of moisture, solvents, or plasticizer.

[0016] Proper storage for film and photographic materials is an important preventive measure that stabilizes delicate or fragile materials and provides basic care for all materials in the collection. Storage cabinetry and enclosures should be chosen and used carefully so that they do not contribute to the deterioration of collection materials. Photographic materials and film can be seriously damaged when stored in cabinets or other containers made of inferior materials that release harmful off gas chemicals, that do not provide adequate physical protection, and/or do not maintain a proper internal environment within the sealed or closed containers. Many commercially available enclosures are labeled “archival” or “acid-free”. However, some of these items may contain lignin, dyes, sizing agents, coatings, plasticizers, or other harmful additives. For a film and photographic material enclosure material to be effective, it should meet or exceed the specifications in ANSI standard IT9.2-1991 (or the latest revision) including the Photographic Activity Test (PAT).

[0017] Because of the very great historical and economic value of the innumerable photographic film libraries throughout the world, may of which contain very rare and one-of-a-kind artifacts, there is currently a great need for an improved photographic film and parer archival storage and preservation container and system of using the same, for overcoming these, and the other problems associated with the archival storage of film and the like.

[0018] Containers of plastic and/or metal having separable covers, which are sealingly fitted and substantially air-tight and thus do not permit off gassing to permeate outside the sealed container, are currently widely used for storing, carrying and shipping reels of motion picture and photographic films and papers, magnetic tape, videotape, and the like. Reel containers of this type are described in U.S. Pat. No. 3,297,153, issued to Fattori, and discussed below. However, these containers present serious problems in the archival storage of motion picture film and the like because they fail to adequately protect the archived film from excessive degradation caused by the buildup of off gases that occur in the internal environment within the sealed or closed containers.

[0019] Typically, currently used storage containers for reels of motion picture film such as those disclosed in U.S. Pat. No. 3,297,153, have focused on maintaining a substantially air-tight environment within the container, wherein off gases produced within the container by either the film, container or both are sealingly prevented from permeating from the container, thereby causing the film stored therein to excessively degrade under these adverse internal environmental conditions.

[0020] The reel container described in U.S. Pat. No. 3,297,153 comprises an open top box having a substantially flat bottom wall and upstanding peripheral side wall. The bottom wall is of a size and shape to receive the flat side of a reel thereon in substantially concentric relation and includes four rounded comers extending beyond the periphery of the reel. A separable fitted cover is provided having a substantially flat top wall shaped to conform to the box bottom wall and downwardly extending side wall which when in the closed position telescopingly engages the box bottom side wall. A pair of registering wells depressed inwardly from the external surfaces of the top wall and bottom wall respectively are disposed at each of the four corners. Each set of registering wells includes a pair of aligned apertures therethrough having registering diametrical enlargements. A tubular rotatable latch is provided which extends from the top well to the bottom well and effectively binds he bottom of box to the container for safe and protected carrying, storing and shipping of any reeled contents.

[0021] Other film reel carriers and similar such containers depicted in the prior art include U.S. Pat. No. 4,476,990 issued to Basili; U.S. Pat. No. 4,109,789 issued to Fattori et al.; U.S. Pat. No. 2,996,178 issued to Forrest; U.S. Pat. No. 2,936,189 issued to Pearson; U.S. Pat. No. 3,077,281 issued to Braverman; U.S. Pat. No. 3,072,280 issued to Spadaro; U.S. Pat. No. 3,169,682 issued to Hollingsworth; U.S. Pat. No. 1,840,822 issued to Ross; U.S. Pat. No. 2,452,230 issued to Derham; and U.S. Pat. No. 2,481,095 issued to Essman.

SUMMARY OF THE INVENTION

[0022] The reel containers in the prior art do not disclose a container having an internal environment favorable for the archival storage and preservation of motion picture film reels and the like, since the containers disclosed in the prior art, unlike the archival storage container disclosed herein, are substantially air-tight when closed, and therefore do not permit the removal of off gases formed therein to permeate the storage container. None of the known prior art and patents taken either singularly or in combination is seen to describe the instant invention as disclosed and claimed. Thus, the subject invention is directed to fire retardant archival film storage and preservation containers that permit off gassing to permeate outside the containers, and used in the archival storage of motion picture and photographic films and papers, videotape, magnetic tape and the like.

[0023] Accordingly, it is an object of the present invention to provide perforated fire retardant archival film storage and preservation containers, and a system of using the same, in the archival storage and preservation of film and the like, wherein off gassing formed within closed storage containers can permeate outside the closed container. The type of artifact that is to be archived and preserved within the archival storage container preferably consists of reels and sheets of motion picture and photographic films, including, but not limited to nitrate, acetate, and polyester film, as well as videotape and magnetic tape. For reels of film, the archival storage containers are preferably 12 or 16 inches in diameter, and are made from a perforated metal to allow off gassing released from film stored therein to permeate outside the closed container. For sheet films, the containers preferably are sized to correspond to the film sheets being stored. The archival storage container generally comprises a bottom receiving portion for receiving a film reel and a separable fitted lid, each shaped to substantially conform in a concentric relationship to the circular shape of a film reel or the rectangular shape of the film sheets. The fitted lid has a downwardly extending peripheral side wall which when in the closed position engages an upstanding side wall of the bottom portion, thereby effectively closing and securing the archival storage container together.

[0024] An additional object of the invention is to provide an archival storage container comprising a fire-retardant material located over the inner surface of the storage container, covering all of the perforations, and functioning as a filter system by preventing dust and particulate matter from entering the closed container, while also permitting out gassing formed therein to permeate the closed container. The flame-retardant material consists of a material that does not substantially release off gases that would contaminate the internal environment within the closed archival storage container, and be deleterious to the film stored therein.

[0025] It is a further object of this invention to provide improved elements and arrangements thereof for the purposes described which are inexpensive, dependable and fully effective in accomplishing its intended purposes. These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0026]FIG. 1 is an exploded view of a film archival storage container according to one embodiment of the present invention;

[0027]FIG. 2 is a bottom perspective view of the bottom portion of the archival storage container according to one embodiment of the present invention;

[0028]FIG. 3 is a top perspective view of the lid of the archival storage container according to one embodiment of the present invention;

[0029]FIG. 4 is a side perspective view of the archival storage container according to one embodiment of the present invention;

[0030]FIG. 5 is an exploded side perspective view of the archival storage container according to one embodiment of the present invention;

[0031]FIG. 6 is an exploded view of the archival storage container further comprising a flame-retardant material located on the inner surfaces of the bottom portion and covering the perforations, according to one embodiment of the present invention.

[0032] Corresponding reference characters indicate corresponding parts throughout the several views. The examples set out herein illustrate preferred embodiments of the invention, in one form, and such examples are not to be construed as limiting the scope of the invention in any manner.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0033] Referring to FIGS. 1-6, a perforated archival motion picture film reel carrier according to the present invention is referred to by the numeral 20. Archival storage containers 20 for reels of motion picture film are preferably 12 or 16 inches in diameter, and are preferably made of a metal, such as stainless steel and the like, that has been perforated according to the invention in order to allow off gassing released by film stored therein to permeate outside the container when in the closed position. Archival storage container 20 is preferably made of 304 stainless steel having a thickness of about 0.032″.

[0034] In a preferred embodiment depicted herein, archival storage container 20 generally comprises bottom receiving portion 22, for receiving a motion picture film reel (not shown) or a similarly shaped reel of other types of material, and separable fitted lid 30. Bottom receiving portion 22 is shaped to substantially conform in a concentric relationship to the circular-shape of a motion picture film reel, and comprises inner surface 23 (FIG. 6), outer surface 29 (FIG. 2), a substantially flat bottom wall region 24 (FIG. 1) having raised embossed regions 50 b that are preferably about {fraction (1/16)}″ high, and upstanding peripheral side wall 26. Bottom wall region 24 and side wall 26 contain perforations or holes 40 from about {fraction (1/16)}″ to about ⅜″ diameter and preferably a diameter of about {fraction (3/16)}″, to permit off gases released by film (not shown) stored within the archival container 20 to permeate outside the container.

[0035]FIG. 1 depicts separable fitted lid 30 shaped to substantially conform to the circular-shape of a motion picture film reel or the like, comprising inner surface 33 (FIG. 6 and outer surface 39 (FIG. 3). Fitted lid 30 has a substantially flat top wall portion 32 having raised embossed regions 50 a that are preferably about {fraction (1/16)}″ high, and downwardly extending peripheral side wall 34 which when in the closed position (FIG. 4) securely engages side wall 26 of bottom portion 22, thereby effectively closing and securing the archival storage container together. Top wall portion 32 of lid 30 contain perforations or holes 40 to permit off gas given off by film (not shown) stored within the in a closed archival container 20 to permeate outside the container. The shape, size and arrangement of the perforations 40 depicted in FIGS. 1-6 are merely representative of one possible embodiment, and can vary in size, shape and arrangement so long as the perforations 40 are capable of performing the off gassing function.

[0036] As depicted in FIGS. 3-5, archival storage container 20 preferably further contains a label viewing region 28, preferably about three inches long, located on the outside of side wall 34 for receiving an identification feature and/or other forms or means of labeling indicia (not shown).

[0037] The location of label viewing region 28 is a preferred embodiment, and can be located on other regions of container 20, such as top outer surface 39 of lid 30 (FIG. 3) or bottom outer surface 29 (FIG. 2) of bottom portion 22. However, label viewing region 28 should be located such that it can be easily read when containers 20 are stored, and should be located on a region of container 20 that does not contain any holes or perforations so as not to interfere with the vital off gassing function provided by the perforations. Additionally the size and/or shape of label viewing region 28 can vary, and is not limited to the preferred size and/or shape depicted in the Figures.

[0038] As depicted in FIG. 6, flame-retardant fabric layer 48 preferably covers the entire inner surface 33 of lid 30 and the entire inner surface 23 of bottom portion 22 of the storage container 20, thereby covering all of the perforations 40 and providing container 20 with flame-retardant properties. The flame-retardant material is preferably an aramid fabric such as Nomex, by DuPont in Wilmington, Del. Flame-retardant fabric layer 48 also functions as a filter system by preventing dust and particulate matter from entering the closed container, while also permitting out gassing to permeate the closed container. The flame-retardant material preferably consists of Nomex O because it does not substantially release any off gases that would contaminate the internal environment within the closed archival storage container 20, and be deleterious to film stored therein.

[0039] Proper archival storage of film and photographic materials is vital to stabilize delicate or fragile materials, and provide effective archival preservation. The system for the archival preservation and storage of reels of motion picture film, magnetic tape, videotape, and the like disclosed herein includes placing the reel containing the desired material to be preserved within archival storage container 20; closing storage container 20 thereby securely housing the reel inside container 20; placing archival storage container 20 housing the reel in an appropriate archival storage facility having an environment for effectively preserving and storing the reels for a desired period of period of time.

[0040] The appropriate environment for effectively archiving and preserving a reel of motion picture and other photographic films comprises maintaining temperature and humidity levels at a constant level and at a maximum of 50° F./10° C. and 50% RH. The appropriate archival and preservation environment further comprises regulating the flow and content of air entering the archival storage area by a proper filtration and purification system so as to remove uwanted gases and particulate matter, as well as regulating the amount and type of light within the archival storage facility. When storing motion picture film on a reel, the film should always be wound evenly, and never too tightly, with the emulsion side out in order to ensure and enhance preservation efforts.

[0041] While the invention has been described with reference to preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the scope of the invention. For example, while archival storage container 20 has been depicted in the preferred embodiment as having a circular-shaped container for the archival storage of motion picture film reels and the like, container 20 can be a variety of shapes and sizes, such as a rectangular shaped box for storing photographic prints, proofs, negatives and the like, in a substantially dust and particulate matter free, flame retardant environment that permits any off gassing released from material stored within a closed storage container 20 to permeate outside the container.

[0042] Therefore, it is intended that the invention not be limited to the particular embodiments disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope and spirit of the appended claims. 

What is claimed:
 1. An archival film storage and preservation container comprising: a bottom receiving portion shaped to substantially conform in a concentric relationship to the shape of a film to be stored therein, having an inner surface, an outer surface, a substantially flat bottom wall region, and an upstanding peripheral side wall; and a separable fitted lid shaped to substantially conform to the shape of the bottom receiving portion and having a substantially flat top wall portion, and a downwardly extending peripheral side wall, wherein the downwardly extending peripheral side wall of the lid securely engages the upstanding peripheral side wall of the bottom receiving portion in order to effectively close the archival storage container; and wherein the top wall portion of the lid, and the bottom wall region and at least one of the peripheral side walls contain perforations to permit off gassing released by film stored within the container to permeate outside the container.
 2. The storage container according to claim 1, further comprising a flame-retardant, particle filter layer located inside the storage container covering all of the perforations.
 3. The storage container according to claim 2, wherein the flame-retardant layer comprises an aramid fabric.
 4. The storage container according to claim 1, wherein the perforations have a diameter within a range from about {fraction (1/16)}″ to about ⅜″.
 5. The storage container according to claim 1, wherein the perforations have a diameter of about {fraction (3/16)}″.
 6. The storage container according to claim 1, wherein the total area of the perforations as a percentage of the total exposed surface area of the container when closed is substantially as shown in the drawings.
 7. The storage container according to claim 1, wherein at least one of the bottom receiving portion and the lid comprise raised embossed and unperforated regions that are at least about {fraction (1/16)}″ higher than the areas that are perforated.
 8. The storage container according to claim 1, further comprising a label viewing region located on an outer surface of the storage container for receiving an identification means.
 9. The storage container according to claim 1, in which the bottom receiving portion and the lid have an outer diameter within a range from about 12 inches to about 16 inches.
 10. The storage container according to claim 1, wherein the storage container is constructed from metal or a metal alloy.
 11. The storage container according to claim 8, wherein the metal alloy comprises stainless steel.
 12. The storage container according to claim 9, wherein the stainless steel has a thickness of about 0.032″.
 13. A film storage and archival preservation system comprising the steps of placing films and/or tapes in archival storage containers according to claim 1, closing the containers; and storing the containers in a controlled environment in appropriately spaced stacks that will enable off gasses permeating the containers to be collected and discharged from the environment.
 14. The system according to claim 11, wherein the appropriate environment comprises the step of maintaining temperature and humidity levels at a constant level and at a maximum of 50° F./10° C. and 50% RH. 